This study investigated underlying mechanisms of the verbal memory disorder associated with chronic alcoholism. Previous investigations have suggested that alcoholics are more vulnerable to interference effects on verbal learning and memory tasks, both with respect to retroactive interference (RI) and proactive interference (PI); this was the hypothesis of the current study. Measures of RI and build-up and release from PI were administered to 31 abstinent male chronic alcoholics and 24 healthy male nonalcoholic control subjects. Alcoholics demonstrated more sensitivity to RI than controls. Additionally, alcoholics displayed a more rapid build-up of PI, although they showed normal release. An increased interference effect was found to be a component of chronic alcoholics’ verbal memory impairment and may differentiate chronic alcoholism from other disorders affecting verbal learning and memory. (JINS, 1996, 2, 141–145.)